After 2 years in development, the Firebird Project today officially releases the much-anticipated version 2.0 of its open source Firebird relational database software during the opening session of the fourth international Firebird Conference in Prague, Czech Republic.

I didn't know what Materialized views where, so googled it. This is what I found someone else posted a few months back, so not sure if 2.0 supports it.
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I think you'll find that materialized views, at least as far as doing refresh-on-commit and query rewriting, are a really advanced feature that only Oracle has. In many warehousing or decision support applications, they are a must have feature that makes the difference between project success and failure.

Assuming you aren't in such a high performance setting, you can often simulate a materialized view by simply populating a transformation table using stored procedures. In such settings, I think either Firebird or PostgreSQL would work fine, cost less, and avoid icky proprietary licence restrictions.
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